化工学报 ›› 2009, Vol. 60 ›› Issue (3): 620-626.

• 多相流和计算流体力学 • 上一篇    下一篇

液液静电雾化特性

张军;郑捷庆   

  1. 集美大学机械工程学院
  • 出版日期:2009-03-05 发布日期:2009-03-05

Characteristics of liquid-liquid electrostatic spray

ZHANG Jun;ZHENG Jieqing   

  • Online:2009-03-05 Published:2009-03-05

摘要: 对水静电雾化弥散于玉米油的液-液雾化过程进行了实验研究。通过拍照对雾滴形态进行了观察。观察表明,不同电压下液-液雾化会呈现出滴状和云状雾化两种较为典型的雾化形态,在两种形态下液滴具有不同的形貌和运动特点,本文给出了两种雾化形态的出现条件及特征描述。通过Winner99颗粒图像分析仪及雾滴尺寸的分布理论,对不同静电电压下雾滴直径的分布规律进行了定量分析。研究结果表明,液-液静电雾化中雾滴的直径分布服从Rosin-Rammler分布规律。随着电压的升高,雾滴直径分布趋向均匀,雾化细度得到改善。与在空气中雾化有所不同,液-液雾化中雾滴分布的概率密度曲线峰值两边呈现出显著的不对称性,小液滴数尺寸分布较窄而大雾滴数的尺寸分布较宽。随着电压的升高,大雾滴尺寸分布有所变窄,概率密度曲线趋近对称。

关键词:

液液静电雾化, 静电电压, 液滴破碎, 雾化形态, 雾滴直径分布

Abstract:

The experimental investigation on a liquid-liquid spray process by dispersing water in corn oil was conducted. The drop formation in the spraying process was observed through analyzing photographs from camera. The observation showed that with increase of electrostatic voltage, the drop formation presented a dripping mode as well as cloudy spraying mode in turn and the drops displayed different characteristics in pattern and movement under two kinds of modes. The existing condition and the characteristics of two modes were presented. The quantitative analysis of spraying droplet diameter distributions was performed at different voltages by means of particle image analyzer and the theory of spraying droplet distribution. The result showed that for liquid-liquid electrostatic spray, the droplet size distribution could be mathematically described by Rosin-Rammler distribution. With increase of voltage, the droplet became fine in size and uniform in size distribution. Comparing with water-in-gas spray, the probability density function curve for droplet size distribution was not symmetrical with respect to its peak value, viz, the diameter distribution for the relatively smaller droplets was narrower than that for other larger droplets. With increase of voltage, the distribution for larger droplets became narrow and the curve shape of probability density function became nearly symmetric.

Key words:

液液静电雾化, 静电电压, 液滴破碎, 雾化形态, 雾滴直径分布